Osteoblasts secrete a characteristic mixture of extracellular matrix proteins including type I collagen as the major component as well as proteoglycans, glycoproteins and γ-carboxylated proteins.
Moreover, immunoprecipitation of HTRA1, a trypsin-like serine protease known to be secreted by cells differentiating into all three major mesenchymal lineages and by stressed cells in general and shown to degrade a number of matrix proteins including collagen, significantly diminished the homing effect.
Extracellular matrix proteins including vitronectin, fibronectin, osteopontin, laminin, and others, bind to particular integrin receptors through an RGD peptide motif [25].
The core motif GxxPG is present 28 times in the sequence of human elastin, and from 3 to 11 times in a number of matrix proteins including fibrillin-1, five collagens, and two tenascins [51].
The presence of HS chains allows interactions with a large number of proteins, including heparin-binding growth factors, plasma proteins such as antithrombin, and extracellular matrix proteins including fibronectin.
As cell adhesion receptors for EPM and other extracellular matrix proteins including fibronectin, laminin, collagen, the roles of integrins such as cell fate determination [44], mitotic machinery regulation [44], [45], in hepatic stem/progenitor cell differentiation and/or morphogenesis, should also be paid more attention in further studies.
The m-AAA and i-AAA proteases probably evolved from an ancestral α-proteobacterial FtsH gene via a duplication mechanism that created a novel and specific pathway for processing of a subset of matrix proteins including Ccp1 and MrpL32 [89], [89].
Extracellular matrix proteins included bovine types I and IV collagen, human fibronectin, mouse laminin, and human vitronectin (Chemicon International).
Matrigel, a loosely defined gel sourced from Engelbreth-Holm-Swarm tumours, is comprised of extracellular matrix (ECM) proteins including laminin-111, collagen IV, heparin sulphate proteoglycans, entactin, fibronectin, growth factors, matrix-degrading enzymes and their inhibitors, and other yet to be defined components [ 6].
In common with most dynamic tissues, the mechanical properties of arteries are determined by the relative composition and architecture of key structural extracellular matrix (ECM) proteins including fibrillar collagens and elastic fibre components.
Fibrosis is characterised by the deposition of the extracellular matrix (ECM) proteins including collagens, structural glycoproteins, sulphated proteoglycans and hyaluronan into the subendothelial space of Disse [1].
